The proposed study is a randomized, controlled trial to determine the efficacy of training intensity and of third party reimbursement on office-based, general dentists' knowledge, attitudes and behaviors related to the assessment and treatment of their patients' tobacco use. Two hundred and fifty dental practices will be randomly selected from a random sample (stratified by state) obtained from a master list maintained by the American Dental Association of all practicing member and nonmember general dentists in California, Arizona, and Nevada. Because dentists who volunteer to possibly be randomized to a group requiring intense training on tobacco cessation treatment may not be representative of dentists providing usual care in the population, we will randomly select 20% of our initial sample of dental practices for a usual-care-comparison arm of the study. The remaining 80% will be enrolled in the intervention arms of the study. Intervention dentists will be randomly assigned to one of four groups: (1) low-intensity training, (2) low-intensity training plus third-party reimbursement, (3) high-intensity training, or (4) high-intensity training plus third-party reimbursement (i.e., a 2x2 factorial design of intensity x reimbursement). Usual care comparison group dentists will receive no intervention. At baseline and at nine months post intervention, all study dentists will complete self-administered questionnaires on their knowledge, attitudes and behaviors related to their assessment and treatment of their patients' tobacco use. Also, at 9-months post-intervention, patient reports of dentists' behavior at target visits will be assessed during telephone interviews, blinded to patients' group assignment. At that time, patients will also report of compliance with dentists' recommendations at those target visits. The primary outcome measures will be patient reports during telephone interviews of dentists' behavior at target visits related to the assessment and treatment of tobacco use. Patient reports clustered within providers will be compared among groups with generalized estimating equation (GEE) models with intensity, reimbursement, and intensity x reimbursement factors. Primary analyses will be based on intention-to-treat principles among the four intervention arms. Secondary analyses will include comparisons to the usual care group.